A New Species of \u3ci\u3eOryzomys\u3c/i\u3e (Rodentia: Muridae) from an Isolated Pocket of Cerrado in Eastern Bolivia

Reliable characterization of a species is an essential step toward eventual reconstruction of phylogenetic alliances among related taxa (Musser et al. 1998). Although characterization of species within the genus Oryzomys has met with some confusion in the past, significant work has taken place to help better define specific limits within this group (Musser et al. 1998; Bonvicino and Moreira 2001; Langguth and Bonvicino 2002). In spite of several recent surveys performed in the eastern Bolivian Panhandle (Emmons 1993; Taber et al. 1997; Brooks et al. 2002), our knowledge of the mammalian fauna in this region is still incomplete, and further studies are warranted. For example, of 1,259 collecting localities in Bolivia analyzed by Anderson (1997), less than two percent are from the eastern panhandle of Santa Cruz Department. Thus, this region constitutes a priority for mammalian exploration and conservation. In mid-April 1999, during an expedition to the eastern Bolivian panhandle (Brooks et al. 2002), we collected a single specimen of the genus Oryzomys that could not be assigned to any known species previously reported for the region in former studies (e.g., Anderson 1993, 1997). Extensive morphological comparisons with deposited voucher specimens revealed that this specimen may represent an undescribed species most closely related to the O. subflavus group (Guy Musser, pers. comm.). To confirm this taxonomic hypothesis, molecular analyses using a portion of the mitochondrial cytochrome-b gene were perfonned to establish phylogenetic relationships. Molecular data supported our conclusion that this specimen represents a new taxon within the genus. In this study, we describe a new form of Oryzomys from the Department of Santa Cruz, Bolivia

Hydrophobic RWGS catalysts: Valorization of CO2-rich streams in presence of CO/H2O

Nowadays, the majority of the Reverse Water Gas Shift (RWGS) studies assume somehow model feedstock (diluted CO2/H2) for syngas production. Nonetheless, biogas streams contain certain amounts of CO/H2O which will decrease the obtained CO2 conversion values by promoting the forward WGS reaction. Since the rate limiting step for the WGS reaction concerns the water splitting, this work proposes the use of hydrophobic RWGS catalysts as an effective strategy for the valorization of CO2-rich feedstock in presence of H2O and CO. Over Fe-Mg catalysts, the different hydrophilicities attained over pristine, N- and B-doped carbonaceous supports accounted for the impact on the activity of the catalyst in presence of CO/H2O. Overall, the higher CO productivity (4.12 μmol/(min·m2)) attained by Fe-Mg/CDC in presence of 20 % of H2O relates to hindered water adsorption and unveil the use of hydrophobic surfaces as a suitable approach for avoiding costly pre-conditioning units for the valorization of CO2-rich streams based on RWGS processes in presence of CO/H2O

Solution blow spun graded dielectrics based on poly(vinylidene fluoride)/multi-walled carbon nanotubes nanocomposites

For the first time polymer-based graded nanocomposites were prepared by solution blow spinning, SBS, looking for new materials with optimal dielectric behavior. SBS was used as the processing method to apply layer by layer multi-walled carbon nanotubes, MWCNT, filled poly(vinylidene fluoride), PVDF, nanocomposites of well controlled compositions. Different configurations in terms of the disposition of layers with distinct concentration of MWCNT were considered. The structure, morphology and thermal behavior of the materials prepared were investigated so as their broadband dielectric properties in order to find and understand possible correlations. Morphological and slight structural changes were observed as a function of MWCNT concentration; however, they do not seem to be the main factors affecting the variations observed in the dielectric behavior of the materials under study. It was demonstrated that a particular design of PVDF based dielectrics, for which there is a particular gradient of MWCNT concentration, importantly increases the permittivity without increasing dielectric losses.The authors appreciate the financial support received from the Ministerio de Economía y Competitividad [MAT2014-59116-C2]; the Universidad Carlos III de Madrid due to Fondos de Investigación de Fco. Javier González Benito [2012/00130/004] and the strategic Action in Composites materials and interphases [2011/00287/002]. Finally, we greatly thank the help given by Dr. Gustavo González-Gaitano (Dept. Chemistry, University of Navarra) conducting an extraordinary work with FTIR spectroscopy

Iridium-Catalyzed Regio- and Diastereoselective Synthesis of C-Substituted Piperazines

Piperazine rings are essential motifs frequently found in commercial drugs. However, synthetic methodologies are mainly limited to N-substituted piperazines, preventing structural diversity. Disclosed herein is a straightforward catalytic method for the synthesis of complex C-substituted piperazines based on an uncommon head-to-head coupling of easily prepared imines. This 100% atom-economic process allows the selective formation of a sole diastereoisomer, a broad substrate scope, and a good functional group tolerance employing a bench-stable iridium catalyst under mild reaction conditions. Key to the success is the addition of N-oxides to the reaction mixture, as they notably enhance the catalytic activity and selectivity

Rate effect in inclined fibre pull-out for smooth and hooked-end fibres: a numerical study

Based on a numerical model to simulate the static behaviour of a smooth fibre extracted from a cementitious matrix, a rate dependent friction law, widely used in earthquake engineering for steady-state slip phenomena, is proposed to capture the rate effect observed in dynamic pull-out tests for both smooth and hooked-end fibres. After calibrating the friction coefficients with the experimental results of smooth fibres, the model is subsequently applied to predict the pullout behaviour of both smooth and hooked-end fibres at different inclination angles (0∘, 30∘ and 60∘) loaded at three different velocities (0.01, 0.1 and 1 mm/s). The global tendency of all the pull-out curves was captured, fibre’s cross sectional deformations were also reproduced remarkably well. Moreover, the developed model helps to cast light on the different mechanisms related to the pull-out process.Ministerio de Ciencia, Innovación y Universidades, Spain, through the projects BIA2015-68678-C2-1-R and RTC-2017-6736-3, is acknowledged. Elisa Poveda appreciates the funding from the International Campus of Excellence CYTEMA, as well as, the University of Castilla-La Mancha, throughout Ayudas para estancias en universidades en el extranjero en 2019 en el ámbito del plan propio de investigación susceptibles de co-financiación por el Fondo FEDER, Programa 010100021 to fund her stay in the University of Minho during 2018 and 2019, respectively. Manuel Tarifa acknowledges the financial support from the Department of Applied Mechanics and Project Engineering, UCLM (2018), and from the Programa propio de I+D+i de la Universidad Politécnica de Madrid para realizar estancias de investigación internacional igual o superior a un mes (2019), with the same purpose. The last two authors acknowledge the support provided by the project ICoSyTec (POCI-01-0145-FEDER-027990) financed by FCT and co-funded by FEDER through the Operational Competitiveness and Internationalization Programme (POCI). The authors thank BEKAERT for the supply of fibre

Size of the fracture process zone in high-strength concrete at a wide range of loading rates

Abstract. Compared with the extensive research on properties of the fracture process zone (FPZ) under quasi-static loading conditions, much less information is available on its dynamic characterization, especially for high-strength concrete (HSC). This paper presents the very recent results of an experimental program aimed at disclosing the loading rate effect on the size and velocity of the (FPZ) in HSC. Eighteen three-point bending specimens were conducted under a wide range of loading rates from from 10 -4 mm/s to 10 3 mm/s using either a servo-hydraulic machine or a self-designed drop-weight impact device. Four strain gauges mounted along the ligament of the specimen were used to measure the FPZ size. Surprisingly, the FPZ size remains almost constant (around 20 mm) when the loading rate varies seven orders of magnitude

Surveillance of Influenza Viruses in Waterfowl Used As Decoys in Andalusia, Spain

A longitudinal study was carried out to determine the seroprevalence of avian influenza viruses (AIVs) in waterfowl used as decoys in Andalusia, southern Spain. A total of 2319 aquatic birds from 193 flocks were analyzed before and after the hunting season 2011–2012. In the first sampling, 403 out of 2319 (18.0%, CI95%: 15.8–19.0) decoys showed antibodies against AIVs by ELISA. The AI seroprevalence was significantly higher in geese (21.0%) than in ducks (11.7%) (P,0.001). Besides, the spatial distribution of AIVs was not homogeneous as significant differences among regions were observed. The prevalence of antibodies against AIVs subtypes H5 and H7 were 1.1% and 0.3%, respectively, using hemagglutination inhibition test (HI). The overall and H5 seroprevalences slightly increased after the hunting period (to 19.2% and 1.4%, respectively), while the H7 seroprevalence remained at the same level (0.3%). The proportion of flocks infected by AIVs was 65.3%, while 11.2% and 4.9% of flocks were positive for H5 and H7, respectively. Viral shedding was not detected in any of the 47 samples positive by both ELISA and HI, tested by RRT-PCR. The individual incidence after the hunting season was 3.4%. The fact that 57 animals seroconverted, 15 of which were confirmed by HI (12 H5 and 3 H7), was indication of contact with AIVs during the hunting period. The results indicate that waterfowl used as decoys are frequently exposed to AIVs and may be potentially useful as sentinels for AIVs monitoring. The seroprevalence detected and the seropositivity against AIVs H5 and H7, suggest that decoys can act as reservoirs of AIVs, which may be of animal and public health concer

Efecto de la velocidade y la inclinación en ensayos de arrancamiento de fibras lisas y conformadas

En el presente artıculo se recopilan los resultados de una reciente campaña experimental sobre el efecto de la velocidad de solicitación y del angulo de inclinación, en ensayos de arrancamiento de fibras de acero de una matriz de hormigon. Para ello, se obtuvieron probetas de placas fabricadas con hormigón auto-compactante de 86 MPa de resistencia. En el programa experimental se emplearon fibras de acero de extremos conformados de nueva generación, sección circular, con ´ 60 mm de longitud y una relación de aspecto de 80. Los ensayos se llevaron a cabo con fibras de extremos conformados ´ y fibras lisas, obteniendo estas últimas mediante el corte del gancho de las primeras. Para ambos tipos, la longitud de ´ fibra embebida en el hormigón fue de 20 mm, estudiando la influencia de la inclinación de la fibra para valores de 0 ´ o, 30o y 60o. Las fibras lisas se obtuvieron cortando el extremo conformado de las anteriores. Los ensayos se realizaron a tres velocidades de solicitación 0.01, 0.1 y 1 mm/s. Como resultado, se obtuvo que las fibras más inclinadas incrementaron la ´ carga necesaria para arrancarlas de la matriz de hormigón en todos los casos, aunque de manera más pronunciada en las ´ fibras lisas. Además, el incremento en la velocidad de solicitación hizo que la carga máxima en el ensayo se incrementará para el caso de las fibras lisas, mientras que permaneció prácticamente estable para las fibras conformadas.This paper summarizes the results obtained in a recent experimental campaign on the effect of the loading pullout rate and the inclination angle of the steel fiber pullout test. For that purpose, specimens were obtained from a self-compacting concrete with a compressive strength of 86 MPa. In the experimental program hooked-end steel fibres of new generation, of circular cross section, length of 60 mm and aspect ratio of 80, were used. Tests were executed with both hooked-end and smooth fibers, being these last ones obtained from the first ones by cutting the hooked-end. For both type of fibers, their embedment length into concrete was 20 mm, and the influence of fiber inclination angle was investigated by adopting values of 0o , 30o and 60o . The tests were performed at displacement rates of 0.01, 0.1 and 1 mm/s. As a result, the peak pullout load increased with the inclination angle, in particular for the smooth series. Furthermore, higher displacement rates produced higher peak forces for the pullout of the smooth fibers, while the peak remained almost stable for hook-end fibers

Agricultural extensification enhances functional diversity but not phylogenetic diversity in Mediterranean olive groves: A case study with ant and bird communities

Agroforests are of well-known importance for biodiversity conservation, especially in the tropics, because they are structurally stable and may resemble natural forests. Previous studies have characterized jointly taxonomic, functional and phylogenetic diversity in these agro-ecosystems to comprehensively examine the mechanisms by which agriculture impacts on biodiversity. However, this approach has been barely applied to other woody crops of economic importance, such as olive grove, which is a remarkable overwintering habitat for frugivorous/insectivorous birds from central and northern Europe, and whose original distribution overlaps with the Mediterranean biodiversity hotspot. We examined the effects of landscape complexity and intensive management practices at a local scale (recurrent plowing and pesticides use) on the functional and phylogenetic diversity of animal communities inhabiting olive groves. Since the response of functional traits or clades may vary across different taxonomic groups, we conducted our study at two levels: ants, which are considered semi-sessile organisms, and birds, which exhibit a high dispersal capacity. In birds, neither management type nor landscape complexity had an effect on phylogenetic diversity (PD) indices. Extensively managed farms harbored bird communities with higher values of functional diversity (FD), but this effect only was evident when considering cultivated (productive) zones within the farm (i.e., infield diversity). Ant assemblages on intensively managed farms exhibited a lower level of phylogenetic clustering than those located in extensive farms, but this effect vanished when excluding non-cultivated zones. Ant functional diversity increased with landscape complexity. Our results indicate that PD and FD exhibit different responses to farming intensification in olive groves. Although intensive management does not erode PD due to the existence of phylogenetic redundancy, the loss of species associated to modern farming leads to a reduction in FD being this indicative of functional complementarity. This study provides evidence that land-use extensification (extensive farming and landscape diversification) promotes more functionally rich assemblages than modern intensive practices in olive groves. Our findings also show the need to set apart the effect of non-cultivated zones (e.g., hedgerows, margins) when evaluating the effectiveness of agri-environment schemes as the joint consideration of non-cultivated and cultivated areas may obscure the benefits of local extensification on infield biodiversity.info:eu-repo/semantics/publishedVersio